package main.leetcode.clockin.June;

import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

/**
 * 139. 单词拆分
 *
 * <p>给定一个非空字符串 s 和一个包含非空单词列表的字典 wordDict，判定 s 是否可以被空格拆分为一个或多个在字典中出现的单词。
 *
 * <p>说明：拆分时可以重输入: s = "applepenapple", wordDict = ["apple", "pen"] 输出: true 解释: 返回 true 因为
 * "applepenapple" 可以被拆分成 "apple pen apple"。 注意你可以重复使用字典中的单词。
 *
 * <p>示例 3：输入: s = "catsandog", wordDict = ["cats", "dog", "sand", "and", "cat"] 输出: false
 */
public class day25 {
    public static void main(String[] args) {
        System.out.println(
                new day25()
                        .wordBreak(
                                "catsandog", Arrays.asList("cats", "dog", "sand", "and", "cat")));
        System.out.println(new day25().wordBreak("leetcode", Arrays.asList("leet", "code")));
        System.out.println(new day25().wordBreak("bb", Arrays.asList("a", "b", "bbb", "bbbb")));
        System.out.println(new day25().wordBreak("cars", Arrays.asList("car", "ca", "rs")));
    }

    public boolean wordBreak(String s, List<String> wordDict) {
        int n = s.length();
        boolean[] dp = new boolean[n + 1];
        Set<String> set = new HashSet<>(wordDict);
        dp[0] = true;
        for (int i = 1; i <= n; ++i) {
            ConcurrentHashMap map = new ConcurrentHashMap();
            map.put(null, null);
            for (int j = 0; j < i; ++j) {
                if (dp[j] && set.contains(s.substring(j, i))) {
                    dp[i] = true;
                    break;
                }
            }
        }
        return dp[n];
    }
}
